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Aluminum alloy materials have been extensively used in long-span roof structures, especially in coastal and industrial buildings containing corrosive matters. In this study, new-type aluminum alloy...

Double skin steel-concrete composite walls offer structural merits over conventional reinforced concrete walls in terms of high strength, good ductility and convenience for construction. The stability of the external steel faceplates is significantly influenced by the types of internal mechanical connectors and the ratio of connector spacing to plate thickness. In this paper, a new type of steel truss was proposed as the fastener to connect the two faceplates. Compressive tests were conducted on three full-scaled composite walls with different truss spacing. The structural response of the walls was comprehensively discussed in terms of failure modes, load-axial displacement response, buckling stress, stiffness, ductility, strength index, load versus out-of-plane displacement response, and load-strain curves. The influences of truss spacing on key parameters were explored in details. The test results showed that the truss spacing could considerably affect the buckling shapes, load-carrying capacity, stiffness and ductility of the specimens.

Double skin steel-concrete composite walls could offer high capacity and stiffness while affiliating the construction. The structural behavior of double skin steel-concrete composite walls under axial compression is largely dependent on the interface bonding between the steel plate and the concrete core. Weak restraint between these two different materials may lead to early local buckling of the steel plate and thus the separation between the steel and concrete surfaces under large compression. Furthermore, the plate thickness is essential to the axial behavior of composite walls. Thin plate may cause early local buckling and thus reduce the axial load capacity. This paper investigates a new type of double skin composite wall. The steel truss constructed by two angles and kinked rebar is acting as the interface connector. Full-scaled tests were conducted on three specimens with different plate thicknesses. The structural behavior of the walls was comprehensively evaluated in terms of load-displacement curve, buckling stress, axial stiffness, ductility ratio, strength index, load-lateral deflection response, and strain distribution. The influences of plate thickness on the structural performance were discussed in details. The test data was compared with the calculated results based on three modern codes. It was found that Eurocode 4 provides the most conservative results while CECS: 2018 offers the most suitable predictions.

The sandwich composite wall with truss connectors is a new type of double-steel-plate composite wall, which consists of two external steel plates, square steel tubes at both ends, and in-fill concrete. The external steel plates are constrained by the steel trusses, thereby possessing superior mechanical performance. In order to study the fire resistance of the sandwich composite wall, 4 full-scaled walls were tested under one-side ISO-834 standard fire, aiming to investigate the effects of axial compression ratio, truss spacing to thickness ratio, and steel plate thickness on the fire resistance of the walls. The temperature, axial displacement and transverse displacement of key parts of the walls were measured. Experimental results indicate that, the walls could maintain sufficient load-bearing capacity as specified by the Class I fire resistance rating of Chinese Code. The fire endurance of the wall was controlled by its thermal insulation. The deformation pattern of the walls under the fire was overall deflection toward the unexposed surface, and the steel plate exposed to the fire experienced obvious local buckling. The axial compression ratio and the truss spacing to thickness ratio had great effects on the deformation behavior of the walls. When the axial compression ratio was reduced from 0.5 to 0.3, the axial deformation of the wall was changed from compression-predominant to expansion-predominant deformation. A larger truss spacing to thickness ratio led to more obvious buckling of the steel plate exposed to the fire. It is recommended to restrict the truss spacing to thickness ratio of the wall in engineering design.

The double skin composite wall (DSCW) with steel truss is an innovative lateral load resisting member which composed of two steel plates, core concrete, concrete-filled steel tubes (CFSTs) as boundary members, and steel truss connectors. The effects of the aspect ratio and the flange wall width on the seismic performance are investigated based on the quasi-static test of full-scale T-shaped DSCWs with steel truss. The failure mode, load-displacement response, shear strength, ductility, energy dissipation, shear deformation, and stress distribution of the specimens were analyzed. The test results showed that the failure mode of the T-shaped DSCW with steel truss specimens with aspect ratios of 2.0 and 2.5 was flexure-shear failure, which was characterized by shear buckling of the steel plate, local buckling, and fracture of the boundary members, and of crushing of core concrete. The T-shaped specimens with a small aspect ratio have a higher shear strength, ductility, energy dissipation capacity, and shear deformation proportion. The T-shaped specimen with a long flange wall also has a higher shear strength, but the ductility, energy dissipation capacity, and shear deformation proportion are small. The stress distribution indicates that the T-shaped specimen is more likely to failure due to the insufficient flexural strength of the boundary member. The theoretical formula for the flexural strength of T-shaped DSCW with steel truss is established, and the validation results show that the formula is accurate and safe.

This paper describes an experimental study to investigate the seismic behavior of double skin composite walls (DSCWs) with steel truss. Based on the results of seven specimens tested at full-scale, the influence of aspect ratio, axial compression ratio, and truss spacing to thickness ratio on the seismic behavior of DSCW with steel truss are considered. The failure mode, load-displacement relationship, strength, ductility, stiffness, energy dissipation capacity, and shear deformation were analyzed. The results showed that the aspect ratio had the most significant influence on the failure mode and seismic behavior of the specimen. For specimens with an aspect ratio of 2.0, shear compression failure dominates, while for specimens with an aspect ratio over 2.0, flexure shear failure dominates. The strength and initial stiffness decreased with the increase of aspect ratio, but the ductility and energy dissipation became better with the increase of aspect ratio. The axial compression had a little positive effect on the strength, but the specimen with a smaller axial compression ratio had better ductility and energy dissipation. The large truss spacing to thickness ratio weakened the external restraint effect of the steel truss on the steel plates, leading to premature buckling and failure of the specimen.

Double-skin composite walls have been increasingly applied in high-rise buildings. The behavior of connection to the wall under seismic action is essential to the performance of the whole structures. This paper investigated the experimental seismic behavior of four proposed connections to an innovative double-skin composite wall. The wall employs steel trusses as internal connectors. Large-scaled cyclic tests were performed on connections with different configurations. The seismic behavior was evaluated in terms of failure mode, hysteretic response, stiffness degradation, ductility, and energy dissipation ability. The test results found that all specimens exhibited stable and plentiful hysteretic performance without noticeable pinching effect. Reasonable stiffness degradation, good ductility and satisfying energy absorbing capacity were also observed. Strain distributions at key locations were analyzed to evaluate the strain development at beam, stiffener, and wall face. It is concluded that the connection with vertical stiffeners has good seismic behavior. The application of vertical plate or additional cover plate is also acceptable. In addition, the use of through plate should be careful as the welding quality is important to the behavior of connections.

Based on the installation process of mega complex steel frame structure in Guangdong Science Center, the engineering features and difficulties are introduced. Then the installation schemes and technologies are described in detail, including installation stages division, installation sequences, installation technology of steel column, main or secondary truss and bow truss. The result indicates that the effect of the installation technology is perfect. The application of this installation technology effectively ensures construction progress, quality and safety.

A new approach, which is suitable for analyzing steel frames-reinforced concrete shear wall hybrid structure considered the semirigid connection for beam and column in horizontal load, is presented. The new simplified method considered the semirigid connection for beam and column in hybrid structure is established. The inter-story drift stiffness of steel frames considered the semirigid connection of beam-column in hybrid structure is derived.The traditional continuum method used in RC frames-shear wall structure is expand to steel frames-reinforced concrete shear wall hybrid structure in the paper.The numerical examples of considered the semirigid connection for beam and column in hybrid structure are analysed. The analysis results show that the proposed method is suitable for adoption in practice.

Dynamic wind pressures acting on structures are complicated functions of both time and space. The proper orthogonal decomposition technique (POD) is a method of detecting a new coordinate system which can most efficiently represent such random wind pressure fields to identify hidden deterministic structures. In this paper, the POD technique is applied to dynamic wind pressures on spatial structures in order to investigate the properties of these pressures and enable to understand the phenomena better. The results indicate that the POD technique can greatly reduce the amount of data that needs to be stored to re-examine the random wind pressure, which can be reconstructed by only a few dominant modes. It requires 5 modes with an accumulative proportion of 70~80% approximately. Moreover, the dominant modes can describe the spatial distributions of the fluctuating wind load effectively.

A second-order inelastic analysis of semirigid connection steel frame structures is developed. Therein, shearing deformation and axial force simultaneously are considered. A new stability function considered shearing deformation and axial force simultaneously is proposed and the analysis methods for steel structure of semirigid connection based on the structural ultimate bearing capacity are established. The calculatical programe of second-order inelastic analysis semirigid connection steel frame structures is compiled. The numerical examples of steel frames for semirigid connection are analysed using the second-order inelastic analysis in the paper. Load–displacements predicted by the proposed analysis compare well with those given by other approaches. The analysis results show that the proposed method is suitable for adoption in practice.